Multiple-disc filters are gaining increasing use in various applications, for example in water irrigation systems for removing foreign particles which may clog the water irrigation devices. Such filters include a stack of filter discs formed with ribbed side faces such as to form narrow filtering channels between the discs when arranged in a stack. Some of the dirt particles are removed and retained at the upstream face of the filter stack facing the filter inlet, the finer dirt particles entering the spaces between the discs being removed and retained in the narrow filtering channels between the discs.
The main object of the present invention is to provide a filter of this type which has a low sensitivity to clogging by dirt particles, which may be more effectively cleaned in a quick and simple manner and, and which has an increased dirt-removing and dirt-holding capacity, as compared to the conventional filters of this type.